South West Water Reduces Storm Spills – What It Means for Cornwall’s Rivers

South West Water cuts storm spills by 40% after key upgrade

South West Water has significantly reduced storm overflow spills in mid-Cornwall, following recent improvements at one of its highest spilling sites. The changes, made in December 2024, have already cut spills by 40% in January 2025 compared to the same period last year.

How Has This Been Achieved?

The improvements were carried out at Fraddon Wastewater Treatment Works, where South West Water installed a storm storage tank designed to hold excess flows during heavy rainfall. Instead of building new infrastructure, the company repurposed an existing lagoon to create additional storage, helping to reduce the frequency of storm overflows.

Andy Pettifer, South West Water’s Operations Manager for West Cornwall, said:

“The improvements at Fraddon show how targeted investment can deliver real environmental benefits. By upgrading existing infrastructure and adding new storm storage capacity, we’ve been able to significantly reduce spills in the area.”

Part of a Bigger Plan

These improvements are just one step in a wider investment programme aimed at reducing storm overflows and improving water quality across the South West. South West Water is also working towards an ambitious goal: becoming the first water company to meet the government’s target of achieving fewer than 10 spills per overflow per year – a full decade ahead of schedule.

The success at Fraddon could mark a major shift in how wastewater management is handled across Cornwall and beyond.